Do the instructions in the last chapter no longer work? What happens if you try to follow them? Does Tumblr give you an error? Is there an error in the JavaScript Console?

The forum software here prevented your code from pasting properly. Can you try again – either using ICE’s share option or pasting the entire contents directly in your reply (be sure to put the three tildes above and below):

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// You would paste your code here...
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For the future, it’s best to start a new topic for new questions – makes it easier for others to find answers.